MSPEC Men's 3D-Crotch Outlast Stretch Tenjiku Boxer Briefs 95% Rayon/ 5% Polyurethane Imported Open Front. Made in Japan. A temperature regulating material developed for NASA: Outlast Technology. Outlast technology was originally developed for NASA in the USA. This revolutionary temperature regulating material helps maintain a comfortable temperature range, at the skin surface, in both cold and hot environments. So you're not too hot, not too cold. The crotch area is spacious. 3-dimensional structure. Feel invigorated. Non-restricted Comfort on the Crotch Area!! Japan technology. Three-dimensionally structured for Crotch Area. Japanese patent No.5120755. YARTS original-goods. MSPEC is designed three-dimensionally to fully support from crotch to testicles and to provide the first ever comfortable underwear for men. Upgrade your comfort. The 5 Comforts: 1. Perfect body fit. Perfect support. 2. No shifting to one side. 3. Breathable. Ventilated. 4. Moisture-absorbing. 5. Freedom to move. Movement free. Japan quality. Fabric: Rayon-95%/ Polyurethane-5% Outlast Stretch Tenjiku. Elastic: Toray "quup" Nylon-83% Polyurethane-11% Polyester-6% Width-1.2 inch. It is using excellent moisture absorption Toray "quup " nylon. Select Size=US-Size/JP-Size: (Waist/Elastic. Inch). M=US-S/JP-M: (30-33/26.3). L=US-M/JP-L: (33-36/29). XL=US-L/JP-LL: (36-39/31.8). XXL=US-XL/JP-3L: (39-42/34.5). XXXL=US-XXL/JP-4L: (42-45/37.2). XXXXL=US-XXXL/JP-5L: (45-48/39.9). Note: MSPEC is made with Japanese size.